This invention relates to a variable displacement mechanism for an internal combustion engine.
FIGS. 1 and 1A illustrate in simplified form a conventional radial engine. The engine shown in FIGS. 1 and 1A comprises a main cylinder structure 2 defining five cylinders 4 and journaling a crankshaft 6. Five pistons 8 are fitted in the cylinders respectively and are connected to the crankshaft by respective connecting rods 10. As the pistons reciprocate in the cylinders in phased relationship, the crankshaft rotates relative to the main cylinder structure.
The stroke of the piston depends on the eccentricity of the crankshaft. In the conventional radial engine, the eccentricity of the crankshaft, and hence the stroke of the piston, is fixed.
The power output and fuel consumption of an internal combustion engine depends on the engine displacement, i.e. the volume that is swept by the pistons during one complete cycle. In order to minimize fuel consumption, it would be desirable to be able to adjust the displacement of an internal combustion engine depending on operating conditions.
One approach to adjusting the engine displacement depending on operating conditions has been to interrupt fuel supply to one or more cylinders in low load conditions so that combustion takes place in fewer than all the cylinders of the engine. This and other approaches to varying engine displacement have not generally met commercial success.